public static string DecryptString(string val, string key, Guid salt)
{
string saltString = salt.ToString("N");
byte[] bytes = Convert.FromBase64String(val);
string decodedString = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
string keySalt = string.Concat(key, saltString);
string shaKey = SHA256CryptoEngine.SHA256Hash(keySalt);
List <char> valArray = new List <char>();
for (int count = 0, total = decodedString.Length; count < total; count++)
{
int dataVal = decodedString[count];
int hashCharVal = shaKey[count % 64];
int finalVal = dataVal - hashCharVal;
valArray.Add((char)finalVal);
}
string joined = string.Join(string.Empty, valArray);
int indexMatch = joined.IndexOf(saltString, StringComparison.OrdinalIgnoreCase);
string password = null;
if (indexMatch > 0)
{
password = joined.Substring(0, indexMatch);
}
return(password);
}
public static string EncryptString(string input, string key, Guid salt)
{
string saltString = salt.ToString("N");
string keySalt = string.Concat(key, saltString);
string shaKey = SHA256CryptoEngine.SHA256Hash(keySalt);
string val = string.Concat(input, saltString);
List <char> valArray = new List <char>();
for (int count = 0, total = val.Length; count < total; count++)
{
int dataVal = val[count];
int hashCharVal = shaKey[count % 64];
int finalVal = dataVal + hashCharVal;
valArray.Add((char)finalVal);
}
string paddingSha = SHA256CryptoEngine.SHA256Hash(val);
int start = valArray.Count % 64;
for (int count = start; count < 64; count++)
{
int dataVal = paddingSha[count];
int hashCharVal = shaKey[count % 64];
int finalVal = dataVal + hashCharVal;
valArray.Add((char)finalVal);
}
string joined = string.Join(string.Empty, valArray);
byte[] bytes = Encoding.UTF8.GetBytes(joined);
string base64 = Convert.ToBase64String(bytes);
return(base64);
}
